What are the recommendations for the Bats (Bilateral Autologous Transplantation of Stem cells) procedure?

Recommendations for Bilateral Autologous Transplantation of Stem Cells (BATS) Procedure

The BATS procedure should only be performed at specialized transplant centers with appropriate accreditation and expertise, using intermediate-intensity conditioning protocols to balance efficacy and safety. 1

Patient Selection and Eligibility

BATS is a specialized form of autologous hematopoietic stem cell transplantation (AHSCT) that requires careful patient selection:

• Patients must have adequate preoperative hemoglobin levels (>110 g/L) 1
• Potential blood loss should exceed 20% of blood volume to justify the procedure 1
• Patients of any age may be considered, but those >45 years require careful cardiac risk assessment 1
• Patients with severe myocardial disease (including moderate-severe left ventricular impairment, unstable angina, severe aortic stenosis, or critical left main stem disease) should undergo the procedure with extreme caution 1

Conditioning Protocols

For optimal outcomes, the following conditioning protocols are recommended:

• Intermediate-intensity conditioning protocols such as BEAM-ATG or cyclophosphamide-ATG are recommended for most settings 1
• Low-intensity regimens (e.g., low-dose cyclophosphamide without serotherapy) are not recommended outside clinical trials due to poor efficacy evidence 1
• High-intensity myeloablative conditioning protocols (e.g., busulfan-cyclophosphamide-ATG) should be avoided outside clinical trials due to higher toxicity risks 1

Procedural Guidelines

When performing the BATS procedure:

1. Maintain strict normovolemia throughout the procedure 1
2. Use appropriate blood collection packs with standard anticoagulant/blood ratio 1
3. Calculate blood volume removal using the formula: V = EBV × (Ho − Hf / Hav) where:
   • V = volume to be removed
   • EBV = estimated blood volume (70 ml/kg body weight)
   • Ho = initial hematocrit
   • Hf = desired hematocrit
   • Hav = average hematocrit (mean of Ho and Hf) 1

Labeling, Storage and Handling

• All units must be clearly labeled with patient's name, hospital number, DOB, collection date/time, and collector's name 1
• Labels must state "UNTESTED BLOOD: FOR AUTOLOGOUS USE ONLY" 1
• Blood must remain with the patient and should not be removed to a blood fridge 1
• Storage limited to 6 hours at room temperature in an insulated container 1
• Pre-infusion identity checks are mandatory, equivalent to standard allogeneic transfusion protocols 1

Post-Transplant Rehabilitation

A structured rehabilitation program should follow the BATS procedure:

1. Pre-habilitation (Weeks -4 to 0): Baseline functional assessment, optimization of physical condition, respiratory function enhancement, and management of symptoms 1

2. Acute Rehabilitation (Weeks 0-4): Patient-centered care with gentle mobilization and respiratory function optimization; exercise intensity should be adapted to platelet counts (contraindicated if platelets <20 × 10⁹/l) 1

3. Subacute Rehabilitation (Weeks 8-12): Intensive inpatient or outpatient rehabilitation to optimize physical fitness and independence 1

4. Community Rehabilitation (Weeks 12-26): Continued recovery at home, promoting independence and potential return to work activities 1

Special Considerations

• Viral marker screening is not routinely required for patients undergoing the procedure 1
• Universal precautions must be observed to protect staff from virus transmission risks 1
• Disposal of used containers and giving sets must follow hospital hazardous waste policies 1
• Blood from patients with known viral infections (HIV, HBV, HCV) must not leave the operating theater 1

Monitoring and Follow-up

• Patients should be monitored for potential complications, particularly those with cardiac risk factors
• Strict infection control measures should be maintained throughout the procedure and recovery period 1
• Individual symptoms (e.g., spasticity) should be promptly assessed and treated 1

The BATS procedure represents a specialized application of autologous stem cell transplantation that requires meticulous attention to patient selection, procedural technique, and post-transplant care to maximize outcomes while minimizing risks.